Exposed ground pad on symbol

[jimtompkins]

Hi Kicadians,

I’m using the CC22650MODA symbol/footprint from UltraLibrarian:

It has 4 “exposed ground pads” under the body of the part. The symbol has 4 rectangular copper pads on the front copper layer (pads 26-29) and 4 round copper shapes on all copper layers (all called “V”). I’m not sure how to connect the pads to a back side ground plane.

The ground pour on the back side doesn’t connect these pads. Kicad does know that they should be connected to ground it seems.

Any suggestions greatly appreciated!

Jim

[Naib]

does the associated electrical symbol have pins 26-29 connected to a net (eg “V” )
also do you really want “via in pad”

[eelik]

Looks like we have another faulty 3rd party footprint. There are graphic lines in copper which don’t belong to any pad.

[John_Pateman]

Would be useful to have the data sheet for this. Unfortunately, the UltraLibrarian footprints often seem to cause problems. The exposed pads should probably all have the same pad number and, as @eelik & @naib point out there are some odd vias and bits of copper. However, this seems to be a problem caused by UltraLibrarian and not KiCad.

[BobZ]

Time to make your own footprint. (??) I have been using only my own footprints…

[BobZ]

I think that thermal “bellypads” or "EP"s generally have vias in pad; multiple ones if there is space. In my hand-soldered boards I like to use a through hole pad in the bellypad and hand-solder it.

[paulvdh]

I do not care much for such external tools to generate footprints. They often seem to be faulty, but if such a footprint is flawless, nobody would make a post on the KiCad forum about it…

Study a bit how such things are handled in KiCad by reviewing a few Footprints from KiCad’s default libraries. There are lots of Footprints with thermal vias. Big pads can be made with a combination of multiple SMT and THT pads with the same pad number. KiCad connects them all, if they are part of a net. And to make them part of a net, you have to add a pin for those pads in the schematic symbol with the same pad number.

I suspect that the yellow THT pads have “V” as pad number, and you have to change that to the same as the SMT pads.

To look at some of the KiCad Footprints, first open the Footprint Editor and then type “thermal” in the search box:

Note that in the screenshot above the pad under the IC has a singe big SMT pads and 6 THT pads and all have a clearly visible pin number, which is one higher then the normal pin count.

KiCad has quite strict rules for it’s own libraries and these result in high quality libraries. You can read more about it in: https://kicad.org/libraries/klc/